Hi,

    I would like to suggest to add an implicit virtual member function that
will return the address of the first grandfather it can find for polymorphic
types (given: grandfather = leftmost parent).  The functionality would be a
lot similar to delete() thru virtual destructors:

#include <iostream>
using namespace std;

struct A { virtual ~A() {} virtual void * implicit() { return this; } };
struct B : A { virtual ~B() {} virtual void * implicit() { return this; } };
struct C : A { virtual ~C() {} virtual void * implicit() { return this; } };
struct D : B, C { virtual ~D() {} virtual void * implicit() { return
this; } };

int main()
{
 void * pV = new D;
 cout << "pV = " << pV << endl;
 // Ex.: pV = 0x80000000

 A * pA = (A*) (C *) (D *) (pV);
 cout << "pA = " << pA << endl;
 // Ex.: pA = 0x80000004

 cout << pA->implicit() << endl;
 // Ex.: pA->implicit() = 0x80000000

 return 0;
}


_That_ would help a lot and I'm sure other people would agree (including
boost::ptr<T>'s author...).



Thanks,

Philippe A. Bouchard



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